Yes, you can help the environment and save money by “greening” your personal computer. It is estimated that you can save $75 a year in energy costs just by making a few easy changes in the way you use—or don’t use—your computer or laptop.

The first and easiest way to save energy? Completely turn off your computer when you know you will not be using it for more than several hours, such as overnight. According to Marc Itzkowitz, director of product management at consumer remote tech support company Support.com.

If you want to avoid long boot-up times, you can put your computer in “sleep,” “standby” or “hibernation” modes, all of which use far less power than a computer in an active “on” state. Itzkowitz says that in a Windows-based PC, standby mode keeps your active files in memory but shuts the power off, while hibernate saves everything to disc and shuts everything off, consuming even less power. 

You can also save a lot of energy by setting your computer and monitor to go to “sleep” when it has been inactive for a certain period of time. Then when you press a button or move the mouse, your screen and computer will come back to life. Sleep mode settings can be programmed with the computer’s power management tools, which can be found in Control Panels or in a Macintosh’s Preferences under the Apple menu. Itzkowitz says the most common mistake people make with power management functions is simply not using them. He recommends putting the monitor to sleep after 10 minutes of nonuse and the computer after 15 minutes. “The largest energy-consuming parts in your computer are hard drive spinning and the lighting for the monitor,” he says. To see how to use power management functions in a Windows Vista operating system, see The Gift that Keeps on Saving.

Don’t just shut the lid of your laptop or notebook computer and expect it to go to sleep, unless your computer is set to sleep when this happens. (This often needs to be programmed in the power management settings. And a screen saver? Fuhgettaboutit. They use more energy than they’re worth and prevent your computer from going to sleep. “The best screen saver is a blank screen,” Itzkowitz says.

Some programs can also prevent a computer from going into sleep, including some games, streaming banner ads on web sites, antivirus software that is set to scan more than you may need it to, virtual private networks, and some peripherals that remain plugged into your computer. These should be unplugged when they are not being used.

Other good advice from the folks at Support.com:

• Increase your memory (RAM) to reduce disk usage, which can be a power draw. 

• If you have a desktop computer, upgrade to an LCD flat-panel monitor instead of a CRT monitor, which can account for half the energy use of a desktop computer. According to the EPA, the use of an Energy Star-qualified monitor can save up to 85 percent of the electricity used by a standard model. 

• Plug all your electronics into a surge protector that you can easily switch off when you leave the room or go to sleep. If you leave them plugged in and the surge protector is switched on, the power supplies for your peripherals can still draw power. (See “Why Your Electronics Suck [Energy].”

• Shut off that printer. Some printers have a sleep mode that consumes a significant amount of power; the printer might look like it’s off, but it isn’t. Most printers will also consume a small amount of power when plugged in and turned off. 

• Replace wireless mice and keyboards with wired mice. Wired mice and wired keyboards use relatively little energy and avoid unnecessary wasting of batteries.

Steven Castle - Contributing Writer

Steven Castle is Electronic House's managing editor. he has been writing about consumer electronics, homes and energy efficiency topics for two decades. He is also the co-founder of GreenTech Advocates.